Abstract: For the contradiction between the increasing requirement of resources and limited load capacity of servers in Massive Multi player Online Game (MMOG)，a Structured Multi-Agent (SMA) model with load balancing was proposed. The theory of P2P MMOG was defined for SMA and three core algorithms which contain node joining algorithm, neighbor discovery algorithm and cross domain algorithm were constructed. These algorithms theoretically guararrtee the consistency of states of all resources. In order to complement the load balancing, SMA assigns the processing licenses of resources to all nodes in an Area of Interest (AOI). hhrough analyzing the scalability, response speed and load consumption etc.，SMA has fine performance.

Key words: MMOG, P2P, Arca of interest, Pastry protocol